Chapter 4 Process and threads

1. Operating System Control Structures

1.1. To manage process and resources

1.2. Construct and maintains tables of information

1.3. 4 different types of table maintained

1.3.1. Memory tables

1.3.2. I/O Tables

1.3.3. File Tables

1.3.4. Process Tables

2. What is process?

2.1. OS Management of Application Execution

2.1.1. Multiple application gain access to resources

2.1.2. Processor switched among multiple applications

2.1.3. Processor and I/O are efficiently used

2.2. Process

2.2.1. A program in execution

2.2.2. A running program

2.2.3. Entity that can assigned and executed on processor

2.2.4. Unit of activity

2.3. Process Element

2.3.1. Program code

2.3.2. Set of data associated with code

2.3.3. Number of element

2.3.3.1. Identifier

2.3.3.2. State

2.3.3.3. Priority

2.3.3.4. Program counter

2.3.3.5. Memory pointers

2.3.3.6. Context data

2.3.3.7. I/O status information

2.3.3.8. Accounting information

2.4. Process Control Block

2.4.1. Contain process element

2.4.2. Created and managed by OS

2.4.3. Key tool to allow support for multitasking

2.4.4. Possible to interrupt running process and resume execution if interruption not occur